Which Factors Contribute to False-Positive, False-Negative, and Invalid Results in Fetal Fibronectin Testing in Women with Symptoms of Preterm Labor?

Objective We assessed the influence of external factors on false-positive, false-negative, and invalid fibronectin results in the prediction of spontaneous delivery within 7 days. Methods We studied symptomatic women between 24 and 34 weeks' gestational age. We performed uni- and multivariable logistic regression to estimate the effect of external factors (vaginal soap, digital examination, transvaginal sonography, sexual intercourse, vaginal bleeding) on the risk of false-positive, false-negative, and invalid results, using spontaneous delivery within 7 days as the outcome. Results Out of 708 women, 237 (33%) had a false-positive result; none of the factors showed a significant association. Vaginal bleeding increased the proportion of positive fetal fibronectin (fFN) results, but was significantly associated with a lower risk of false-positive test results (odds ratio [OR], 0.22; 95% confidence intervals [CI], 0.12-0.39). Ten women (1%) had a false-negative result. None of the investigated factors was significantly associated with a significantly higher risk of false-negative results. Twenty-one tests (3%) were invalid; only vaginal bleeding showed a significant association (OR, 4.5; 95% CI, 1.7-12). Conclusion The effect of external factors on the performance of qualitative fFN testing is limited, with vaginal bleeding as the only factor that reduces its validity.

Neonatal and obstetric outcomes in diet- and insulin-treated women with gestational diabetes mellitus: a retrospective study.

BACKGROUND: To evaluate the neonatal and obstetric outcomes of pregnancies complicated by gestational diabetes mellitus (GDM). Screening and treatment - diet-only versus additional insulin therapy - were based on the 2010 national Dutch guidelines. METHODS: Retrospective study of the electronic medical files of 820 singleton GDM pregnancies treated between January 2011 and September 2014 in a university and non-university hospital. Pregnancy outcomes were compared between regular care treatment regimens -diet-only versus additional insulin therapy- and pregnancy outcomes of the Northern region of the Netherlands served as a reference population. RESULTS: A total of 460 women (56 %) met glycaemic control on diet-only and 360 women (44 %) required additional insulin therapy. Between the groups, there were no differences in perinatal complications (mortality, birth trauma, hyperbilirubinaemia, hypoglycaemia), small for gestational age, large for gestational age (LGA), neonate weighing >4200 g, neonate weighing ≥4500 g, Apgar score <7 at 5 min, respiratory support, preterm delivery, and admission to the neonatology department. Neonates born in the insulin-group had a lower birth weight compared with the diet-group (3364 vs. 3467 g, p = 0.005) and a lower gestational age at birth (p = 0.001). However, birth weight was not different between the groups when expressed in percentiles, adjusted for gestational age, gender, parity, and ethnicity. The occurrence of preeclampsia and gestational hypertension was comparable between the groups. In the insulin-group, labour was more often induced and more planned caesarean sections were performed (p = 0.001). Compared with the general obstetric population, the percentage of LGA neonates was higher in the GDM population (11.0 % vs.19.9 %, p = <0.001). CONCLUSIONS: Neonatal and obstetric outcomes were comparable either with diet-only or additional insulin therapy. However, compared with the general obstetric population, the incidence of LGA neonates was significantly increased in this GDM cohort.

Randomized comparison of nifedipine and placebo in fibronectin-negative women with symptoms of preterm labor and a short cervix (APOSTEL-I Trial).

OBJECTIVE: To evaluate whether tocolysis with nifedipine can be omitted in women with symptoms of preterm labor, a shortened cervix, and negative fetal fibronectin test. STUDY DESIGN: A randomized noninferiority trial was performed in all Dutch perinatal centers. Women with symptoms of preterm labor between 24 and 34 weeks, intact membranes, cervical length between 10 and 30 mm, and negative fibronectin test were randomly allocated to nifedipine (80 mg/day) or placebo. The primary outcome was delivery within 7 days. Secondary outcomes were severe neonatal morbidity and mortality. We also followed all eligible nonrandomized women. RESULTS: We allocated 37 women to nifedipine and 36 women to placebo. In the nifedipine group, three women (8.1%) delivered within 7 days, compared with one woman (2.8%) in the placebo group (difference -5.3%; one-sided 95% confidence limit 4.5%). Median gestational age at delivery were respectively 37 + 0 (interquartile range [IQR] 34 + 6 to 38 + 5) and 38 + 2 (IQR 37 + 0 to 39 + 6) weeks (p = 0.008). In the nifedipine group, three pregnancies (8.1%) had a poor outcome; there were no poor outcomes in the placebo group. We observed similar trends in eligible nonrandomized women. CONCLUSION: In symptomatic women with preterm labor, a shortened cervix, and negative fibronectin test, placebo treatment is not inferior to tocolysis with nifedipine.

Uteroplacental blood flow, cardiac function, and pregnancy outcome in women with congenital heart disease.

BACKGROUND: Pregnant women with congenital heart disease (CHD) are susceptible to cardiovascular, obstetric, and offspring complications. In women with CHD, cardiac dysfunction may compromise uteroplacental flow and contribute to the increased incidence of obstetric and offspring events. METHODS AND RESULTS: We performed a prospective multicenter cohort study of pregnant women with CHD and healthy pregnant women. We compared clinical, laboratory, echocardiographic, and uteroplacental Doppler flow (UDF) parameters at 20 and 32 weeks gestation, and pregnancy outcome. We related cardiovascular parameters to UDF parameters and pregnancy outcome in women with CHD. We included 209 women with CHD and 70 healthy women. Cardiovascular parameters (N-terminal pro-B-type natriuretic peptide, left and right ventricular function) differed between both groups. UDF parameters were impaired in CHD women (umbilical artery pulsatility and resistance index at 32 weeks in CHD versus healthy women, P=0.0085 and P=0.017). The following cardiovascular parameters prepregnancy and at 20 weeks gestation were associated with UDF (umbilical artery resistance index) at 32 weeks at multivariable analysis: (1) right ventricular function (tricuspid annular plane systolic excursion) (P=0.002), (2) high N-terminal pro-B-type natriuretic peptide (P=0.085), (3) systemic (P=0.001), and (4) pulmonary (P=0.045) atrioventricular valve regurgitation. Women with CHD had more obstetric (58.9% versus 32.9%, P<0.0001) and offspring events (35.4% versus 18.6%, P=0.008) than healthy women. Impaired UDF was associated with adverse obstetric and offspring outcome. CONCLUSIONS: UDF parameters are abnormal in pregnant women with CHD. Cardiovascular function is associated with an abnormal pattern of UDF. Compromised UDF may be a key factor in the high incidence of offspring and obstetric complications in this population.

Effect of maintenance tocolysis with nifedipine in threatened preterm labor on perinatal outcomes: a randomized controlled trial.

IMPORTANCE: In threatened preterm labor, maintenance tocolysis with nifedipine, after an initial course of tocolysis and corticosteroids for 48 hours, may improve perinatal outcome. OBJECTIVE: To determine whether maintenance tocolysis with nifedipine will reduce adverse perinatal outcomes due to premature birth. DESIGN, SETTING, AND PARTICIPANTS: APOSTEL-II (Assessment of Perinatal Outcome with Sustained Tocolysis in Early Labor) is a double-blind, placebo-controlled trial performed in 11 perinatal units including all tertiary centers in The Netherlands. From June 2008 to February 2010, women with threatened preterm labor between 26 weeks (plus 0 days) and 32 weeks (plus 2 days) gestation, who had not delivered after 48 hours of tocolysis and a completed course of corticosteroids, were enrolled. Surviving infants were followed up until 6 months after birth (ended August 2010). INTERVENTION: Randomization assigned 406 women to maintenance tocolysis with nifedipine orally (80 mg/d; n = 201) or placebo (n = 205) for 12 days. Assigned treatment was masked from investigators, participants, clinicians, and research nurses. MAIN OUTCOME MEASURES: Primary outcome was a composite of adverse perinatal outcomes (perinatal death, chronic lung disease, neonatal sepsis, intraventricular hemorrhage >grade 2, periventricular leukomalacia >grade 1, or necrotizing enterocolitis). Analyses were completed on an intention-to-treat basis. RESULTS: Mean (SD) gestational age at randomization was 29.2 (1.7) weeks for both groups. Adverse perinatal outcome was not significantly different between groups: 11.9% (24/201; 95% CI, 7.5%-16.4%) for nifedipine vs 13.7% (28/205; 95% CI, 9.0%-18.4%) for placebo (relative risk, 0.87; 95% CI, 0.53-1.45). CONCLUSIONS AND RELEVANCE: In patients with threatened preterm labor, nifedipine-maintained tocolysis did not result in a statistically significant reduction in adverse perinatal outcomes when compared with placebo. Although the lower than anticipated rate of adverse perinatal outcomes in the control group indicates that a benefit of nifedipine cannot completely be excluded, its use for maintenance tocolysis does not appear beneficial at this time. TRIAL REGISTRATION: trialregister.nl Identifier: NTR1336.

Pregnancy in women with corrected tetralogy of Fallot: occurrence and predictors of adverse events.

BACKGROUND: In women with corrected tetralogy of Fallot (ToF), pregnancy is associated with maternal cardiac, obstetric, and offspring complications. Our aim is to investigate the magnitude and determinants of pregnancy outcome in women with corrected ToF. METHODS: In this retrospective international multicenter study using 2 congenital heart disease registries, 204 women with corrected ToF were identified. Within this group, 74 women had 157 pregnancies, including 30 miscarriages and 4 terminations of pregnancy. Detailed information on each completed pregnancy (n = 123) was obtained using medical records and supplementary interviews. RESULTS: Cardiovascular events occurred during 10 (8.1%) pregnancies, mainly (supra)ventricular arrhythmias. Obstetric and offspring events occurred in 73 (58.9%) and 42 (33.9%) pregnancies, respectively, including offspring mortality in 8 (6.4%). The most important predictor was use of cardiac medication before pregnancy (odds ratio for cardiac events 11.7, 95% CI 2.2-62.7; odds ratio for offspring events 8.4, 95% CI 1.4-48.6). In pregnancies with cardiovascular events, significantly more small-for-gestational-age children were born (P value < .01). CONCLUSIONS: Cardiovascular, obstetric, and offspring events occur frequently during pregnancies in women with ToF. Maternal use of cardiovascular medication is associated with pregnancy outcome, and maternal cardiovascular events during pregnancy are highly associated with offspring events.

Associations between cardiovascular parameters and uteroplacental Doppler (blood) flow patterns during pregnancy in women with congenital heart disease: Rationale and design of the Zwangerschap bij Aangeboren Hartafwijking (ZAHARA) II study.

BACKGROUND: Previous research has shown that women with congenital heart disease (CHD) are more susceptible to cardiovascular, obstetric, and offspring events. The causative pathophysiologic mechanisms are incompletely understood. Inadequate uteroplacental circulation is an important denominator in adverse obstetric events and offspring outcome. The relation between cardiac function and uteroplacental perfusion has not been investigated in women with CHD. Moreover, the effects of physiologic changes on pregnancy-related events are unknown. In addition, long-term effects of pregnancy on cardiac function and exercise capacity are scarce. METHODS: Zwangerschap bij Aangeboren Hartafwijking (ZAHARA) II, a prospective multicenter cohort study, investigates changes in and relations between cardiovascular parameters and uteroplacental Doppler flow patterns during pregnancy in women with CHD compared to matched healthy controls. The relation between cardiovascular parameters and uteroplacental Doppler flow patterns and the occurrence of cardiac, obstetric, and offspring events will be investigated. At 20 and 32 weeks of gestation, clinical, neurohumoral, and echocardiographic evaluation and fetal growth together with Doppler flow measurements in fetal and maternal circulation are performed. Maternal evaluation is repeated 1 year postpartum. IMPLICATIONS: By identifying the factors responsible for pregnancy-related events in women with CHD, risk stratification can be refined, which may lead to better pre-pregnancy counseling and eventually improve treatment of these women.

Development of muscle ultrasound density in healthy fetuses and infants.

Muscle ultrasound density (MUD) is a non-invasive parameter to indicate neuromuscular integrity in both children and adults. In healthy fetuses and infants, physiologic MUD values during development are still lacking. We therefore aimed to determine the physiologic, age-related MUD trend of biceps, quadriceps, tibialis anterior, hamstrings, gluteal and calf muscles, from pre- to the first year of postnatal life. To avoid a bias by pregnancy-related signal disturbances, we expressed fetal MUD as a ratio against bone ultrasound density. We used the full-term prenatal MUD ratio and the newborn postnatal MUD value as reference points, so that MUD development could be quantified from early pre- into postnatal life. Results: During the prenatal period, the total muscle group revealed a developmental MUD trend concerning a fetal increase in MUD-ratio from the 2nd trimester up to the end of the 3rd trimester [median increase: 27% (range 16-45), p < .001]. After birth, MUD-values increased up to the sixth month [median increase: 11% (range -7-27), p = 0.025] and stabilized thereafter. Additionally, there were also individual MUD characteristics per muscle group and developmental stage, such as relatively low MUD values of fetal hamstrings and high values of the paediatric gluteus muscles. These MUD trends are likely to concur with analogous developmentally, maturation-related alterations in the muscle water to peptide content ratios.

Perinatal outcome of monoamniotic twin pregnancies.

OBJECTIVE: To study perinatal mortality and neonatal morbidity in a large cohort of monoamniotic twin pregnancies with special emphasis to the gestational age-specific mortality. METHODS: The study included monoamniotic twin pregnancies delivered in 10 perinatal centers in the Netherlands between January 2000 and December 2007. RESULTS: A total of 98 monoamniotic pregnancies were included. The perinatal mortality rate (20 weeks of gestation through 28 days of life) was 19%; after exclusion of fetuses with lethal anomalies, the rate was 17%. After 32 weeks of gestation, only two pregnancies were complicated by perinatal mortality (4%). The incidence of twin-twin transfusion syndrome was 6%. The incidence of congenital heart anomalies and cerebral injury was 4% and 5%, respectively. CONCLUSION: The current incidence of perinatal mortality in monoamniotic twins is considerably lower than in previous decades, but it is still high and occurs throughout pregnancy. LEVEL OF EVIDENCE: III.

Cost-effectiveness of fibronectin testing in a triage in women with threatened preterm labor: alleviation of pregnancy outcome by suspending tocolysis in early labor (APOSTEL-I trial).

BACKGROUND: At present, women with threatened preterm labor before 32 weeks of gestation are, after transfer to a perinatal center, treated with tocolytics and corticosteroids. Many of these women are treated unnecessarily. Fibronectin is an accurate predictor for the occurrence of preterm birth among women with threatened preterm labor. We will assess whether triage of these women with fibronectin testing, cervical length or their combination is cost-effective. METHODS/DESIGN: We will investigate a prospective cohort of women referred to a perinatal centre for spontaneous threatened preterm labor between 24 and 34 weeks with intact membranes. All women will be tested for fibronectin and cervical length. Women with a cervical length <10 mm and women with a cervical length between 10-30 mm in combination with a positive fibronectin test will be treated with tocolytics according to local protocol. Women with a cervical length between 10-30 mm in combination with a negative fibronectin test will be randomised between treatment with nifedipine (intervention) and placebo (control) for 48 hours. Women with a cervical length > 30 mm will be managed according to local protocol. Corticosteroids may be given to all women at the discretion of the attending physician. Primary outcome measure will be delivery within 7 days. Secondary outcome measures will be neonatal morbidity and mortality, complications of tocolytics, costs and health related quality of life. The analysis will be according to the intention to treat principle. We anticipate the probability on preterm birth within 7 days in the group of women with a negative fibronectine test to be 5%. Two groups of 110 women will be needed to assure that in case of non-inferiority the difference in the proportion of preterm deliveries < 7 days will be within a prespecified boundary of 7.5% (one sided test, beta 0.2, alpha 0.05). Data obtained from women with a positive and negative fibronectin tests in both the cohort study and the trial will be integrated in a cost-effectiveness analysis that will assess economic consequences of the use of fibronectin. DISCUSSION: This study will provide evidence for the use of fibronectin testing as safe and cost-effective method in a triage for threatened preterm labor. TRIAL REGISTRATION: Nederlands Trial Register (NTR) number 1857, http://www.trialregister.nl.

Severe pregnancy-induced deterioration of truncal valve regurgitation in an adolescent patient with repaired truncus arteriosus.

Truncus arteriosus, a rare and complex congenital heart disease, is hallmarked by a single great vessel (truncus) that arises over a large ventricular septal defect and provides both the pulmonary and systemic circulation. Pregnancy reports after repair for truncus arteriosus are scarce. Therefore, the maternal and offspring outcomes are unknown. We report the outcome of a pregnancy in an 18-year-old woman with repaired truncus arteriosus. Despite severe and symptomatic deterioration of truncal valve regurgitation, she successfully delivered a healthy child, and the valve function recovered within 2 weeks postpartum.

Cardiovascular biochemical risk factors among women with spontaneous preterm delivery.

OBJECTIVE: To determine whether women delivering preterm have unfavorable cardiovascular profiles as compared with women who deliver at term. METHODS: A prospective observational cohort study enrolled 165 women with spontaneous preterm delivery (sPTD) at 24+0 and 36+6 gestational weeks in three perinatal care centers in The Netherlands between August 2012 and August 2014. Total cholesterol, triglycerides, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, apolipoprotein, glucose, and homocysteine were measured within 24 hours after delivery. Lipids and cardiovascular biochemical risk factors were compared between women with sPTD and an external comparison group of 30 women with term delivery via analysis of covariance. RESULTS: Mean gestational age at delivery was 30.7 ± 3.6 weeks in the sPTD group and 40.3 ± 1.3 weeks in the reference group. Data were adjusted for body mass index, age, and center. As compared with the reference group, total cholesterol and LDL-cholesterol levels were lower and glucose levels were higher among women with sPTD. CONCLUSION: An association between sPTD and unfavorable lipids and cardiovascular biochemical risk factors was not established. The higher levels of glucose in the sPTD group might be due to increased insulin resistance, which is associated with a higher risk of sPTD.

Biological versus mechanical heart valve prosthesis during pregnancy in women with congenital heart disease.

BACKGROUND: We evaluate pregnancy outcome and anticoagulation regimes in women with mechanical and biological prosthetic heart valves (PHV) for congenital heart disease. METHODS: Retrospective multicenter cohort studying pregnancy outcomes in an existing cohort of patients with PHV. RESULTS: 52 women had 102 pregnancies of which 78 pregnancies (46 women) ≥20 weeks duration (59 biological, 19 mechanical PHV). Miscarriages (n = 19, ≤20 weeks) occurred more frequently in women using anticoagulation (P < .05). During 42% of pregnancies of women with mechanical PHV a combined low molecular weight heparin (LMWH) vitamin-K-antagonist anticoagulation regime was used (n = 8). Overall, cardiovascular, obstetric and fetal/neonatal complications occurred in 17% (n = 13), 68% (n = 42) and 42% (n = 27) of the pregnancies. Women with mechanical PHV had significantly higher cardiovascular (12% vs 32%, P < .05), obstetric (59% vs 85%, P = .02) and fetal/neonatal (34% vs 61%, P < .05) complication rates than women with biological PHV. This was related to PHV thrombosis (n = 3, P < .02), post-partum hemorrhage (P < .02), cesarean section (P < .02), low birth weight and small for gestational age (both P < .05). PHV thrombosis occurred in 3 pregnancies, including 2/5 pregnancies with pulmonary mechanical PHV. PHV thrombosis was related to necessary cessation of anticoagulation therapy or insufficient monitoring of LMWH. Other cardiovascular complications occurred equally frequent in both groups. CONCLUSION: Complications occur more often in pregnancies of women with a mechanical PHV than in women with a biological PHV, mainly caused by PHV thrombosis and bleeding complications. Meticulous monitoring of anticoagulation in pregnant women is necessary. Women with a pulmonary mechanical PHV are at high risk of complications.

Fertility, pregnancy, and delivery after biventricular repair for pulmonary atresia with an intact ventricular septum.

The objective of the present study to investigate fertility, pregnancy, and delivery in women with biventricular repair for pulmonary atresia with an intact ventricular septum (PAIVS). Using a nationwide registry (CONCOR), 37 patients with pulmonary atresia were identified, 6 of whom (aged 21 to 34 years) had biventricular repair for PAIVS. Three PAIVS patients had a total of 5 pregnancies, including 1 abortion and 1 ectopic pregnancy. Besides minor noncardiac complications, the 3 live-birth pregnancies were successful. None of the women reported infertility or irregularities (hypermenorrhea, dysmenorrhea, polymenorrhoea, oligomenorrhea, or amenorrhea) of their natural menstrual cycle. In conclusion, successful pregnancy in women with biventricular repair for PAIVS is possible, and only minor complications were observed. Infertility and menstrual cycle disorders do not appear to be more prevalent than usual.

Pregnancy after biventricular repair for pulmonary atresia with ventricular septal defect.

Information on pregnancy and delivery in women with biventricular repair for isolated noncomplex pulmonary atresia with a ventricular septal defect (PAVSD) is limited. Using a nationwide congenital heart disease registry (CONgenital CORvitia [CONCOR]), 9 women with biventricular repair for PAVSD (aged 21 to 38 years) were identified. Ten pregnancies were observed in 5 different women with PAVSD, including 3 spontaneous miscarriages. Clinically significant (non)cardiac complications were documented in 3 of 7 completed pregnancies. These complications were: (1) atrioventricular reentry tachycardia with symptomatic right-sided heart failure; (2) eclampsia with hemolysis, elevated liver enzymes, and low platelets syndrome further complicated by abruptio placentae leading to premature delivery of a small-for-gestational-age child; and (3) premature delivery due to cervical insufficiency with antepartum demise of an immature child. Furthermore, none of the women reported infertility. Moreover, none of the women reported irregularities of their natural menstrual cycle (age at menarche 13 years; cycle duration 28 days), with the exception of delayed menarche (>16 years) in 2 patients. In conclusion, successful pregnancy in patients with biventricular repair of PAVSD is possible, although often complicated by serious clinically significant events. Infertility and menstrual cycle disorders do not appear to be more prevalent, except for a high incidence of primary amenorrhea.

The amplitude of the Achilles tendon reflex in infants is related to body position.

In this study, we investigated whether the Achilles tendon reflex (ATR) in healthy infants is modulated by changes in body position (prone vs. supine). The amplitude of the ATR was compared at postnatal day 1, months 2, 3 and 6, while infants were placed in prone and supine position. The ATR was considered "positive" when at least 1 of 20 tendon taps evoked a visible contraction of the ankle plantar flexor muscles. At 6 months, the amplitude and latency of the ATR were evaluated by electromyographic (EMG) recordings of the (lateral and medial) gastrocnemius muscle, with the infant in prone and supine position. At postnatal day 1, the clinical ATR response was more frequently present in prone than supine position (14/16 or 88% vs. 4/16 or 25%, respectively, p < 0.01). From 2 months onwards, the frequencies of positive ATRs were no longer significantly different between prone (14/14 or 100%) and supine position (10/14 or 67%). However, based on the EMG recordings at 6 months, the ATR amplitude was higher in prone compared to supine position (n=8, median 5.5 mV, range 4.7-6.6 mV; and median 3.8 mV, range 2.3-5.6 mV, p < 0.05). We conclude that the ATR response in healthy infants is more pronounced in prone than in supine position, either when clinically (visually) assessed during routine tendon tapping or when neurophysiologically assessed during surface EMG recording.

The impact of fetal gender and ethnicity on the risk of spontaneous preterm delivery in women with symptoms of preterm labor.

OBJECTIVE: The objective of this study is to evaluate the relation among fetal gender, ethnicity, and preterm labor (PTL) and preterm delivery (PTD). METHODS: A secondary analysis was performed of a prospective cohort study including women with symptoms of PTL between 24 and 34 weeks. The proportion of women carrying a male or female fetus at the onset of PTL was calculated. Gestational age at delivery and risk of PTD of both fetal genders was compared and interaction of fetal gender and maternal ethnicity on the risk of PTD was evaluated. RESULTS: Of the 594 included women, 327 (55%) carried a male fetus. Median gestational age at delivery in women pregnant with a male fetus was 37 5/7 (IQR 34 4/7-39 1/7) weeks compared with 38 1/7 (IQR 36 0/7-39 5/7) weeks in women pregnant with a female fetus (p = 0.032). The risk of PTD did not differ significantly. In Caucasians, we did find an increased risk of PTD before 37 weeks in women pregnant with a male fetus (OR 1.9 (95% CI 1.2-3.0)). CONCLUSIONS: The majority of women with PTL are pregnant with a male fetus and these women deliver slightly earlier. Race seems to affect this disparity.

Comparison of the Actim Partus test and the fetal fibronectin test in the prediction of spontaneous preterm birth in symptomatic women undergoing cervical length measurement.

OBJECTIVE: To compare the accuracy of the Actim Partus test and fetal fibronectin (fFN) test in the prediction of spontaneous preterm delivery within seven days in symptomatic women undergoing cervical length measurement. STUDY DESIGN: We performed a post-hoc analysis on frozen samples of a nationwide cohort study in all 10 perinatal centres in the Netherlands. We selected samples from women with signs of preterm labour between 24 and 34 weeks of gestational age and a cervical length below 30mm. Delivery within seven days after initial assessment was the primary endpoint. We calculated sensitivity, specificity, and positive and negative predictive values for the combination of both the Actim Partus test and fFN test with cervical length. A test was considered positive in case of a cervical length between 15 and 30mm with a positive Actim Partus or fFN test, and a cervical length below 15mm regardless the test result. RESULTS: In total, samples of 350 women were tested, of whom 69 (20%) delivered within seven days. Eighty-four women had a positive Actim Partus test and 162 women a positive fFN test, of whom 54 (64%) and 63 (39%) delivered within seven days, respectively. Ninety-seven women had a cervical length below 15mm, of whom 50 (52%) delivered within seven days. Sensitivity, specificity, positive and negative predictive values of combining cervical length with the Actim Partus test or the fFN test were 91%, 75%, 47% and 97%, and 96%, 58%, 36% and 98%, respectively. CONCLUSION: According to this post-hoc study, in combination with cervical length, the Actim Partus test could be used as an alternative for the fFN test to identify women who will not deliver within seven days after presentation. Further evidence should be collected in a prospective comparative study.

Predictive Factors for Delivery within 7 Days after Successful 48-Hour Treatment of Threatened Preterm Labor.

Objective The aim of this study was to assess which characteristics and results of vaginal examination are predictive for delivery within 7 days, in women with threatened preterm labor after initial treatment. Study Design A secondary analysis of a randomized controlled trial on maintenance nifedipine includes women who remained undelivered after threatened preterm labor for 48 hours. We developed one model for women with premature prelabor rupture of membranes (PPROM) and one without PPROM. The predictors were identified by backward selection. We assessed calibration and discrimination and used bootstrapping techniques to correct for potential overfitting. Results For women with PPROM (model 1), nulliparity, history of preterm birth, and vaginal bleeding were included in the multivariable analysis. For women without PPROM (model 2), maternal age, vaginal bleeding, cervical length, and fetal fibronectin (fFN) status were in the multivariable analysis. Discriminative capability was moderate to good (c-statistic 0.68; 95% confidence interval [CI] 0.60-0.77 for model 1 and 0.89; 95% CI, 0.84-0.93 for model 2). Conclusion PPROM and vaginal bleeding in the current pregnancy are relevant predictive factors in all women, as are maternal age, cervical length, and fFN in women without PPROM and nulliparity, history of preterm birth in women with PPROM.

Prescribing patterns of antenatal corticosteroids in women with threatened preterm labor.

OBJECTIVE: To assess the impact of cervical length (CL) measurement and fetal fibronectin testing (fFN) on the clinicians' decision to prescribe antenatal corticosteroids (ACS) to women with symptoms of preterm labor. STUDY DESIGN: This is a secondary analysis of a prospective cohort study including women with symptoms of preterm labor and intact membranes between 24 and 34 weeks' gestation. We compared the proportion prescribed and completed ACS courses, preterm delivery within seven days and median intervals from ACS to delivery in four groups: group 1 CL<10 mm, group 2 CL 10-30 mm and positive fFN, group 3 CL 10-30 mm and negative fFN, group 4 CL>30 mm. RESULTS: ACS were prescribed to 63/65 (97%) women in group 1, 176/192 (91%) in group 2, 111/172 women (65%) in group 3 and 55/242 (23%) in group 4. In group 1, 42 (65%) women delivered within seven days, compared to 34 (18%) in group 2, 6 (3%) in group 3 and 3 (1%) in group 4. Median intervals between ACS and delivery were 6 days (IQR 3-61 days), 44 days (IQR 17-69 days), 53 days (IQR 37-77 days) and 66 days (IQR 43-78 days) in group 1, 2, 3 and 4 respectively. CONCLUSION: ACS were prescribed frequently to women with a CL of 10-30 mm and a negative fFN test or a CL>30 mm. There is room for improvement in the prescription of ACS in these low risk women.